More than 200 mud-spattered festival-goers - many of them wearing Metallica T-shirts - lined up at the rear of the enormous platform behind Lars Ulrich's drum kit, cheering and dancing throughout the gig.The choice of headline act raised eyebrows in the run-up to the event, with many critics arguing a heavy metal band has no place at Glastonbury, but the Enter Sandman hitmakers closed the second day of the festival in style with a high-octane set that thrilled the crowd.During the show, frontman James Hetfield addressed the controversy over the band's inclusion, telling the crowd: "Metallica is grateful to be invited to such an event called Glastonbury. We're very proud to be here and to be representing, can I say, the heavier sides of music, alright? I know it's all represented here so why not heavy rock, heavy metal, huh? It's about time."He then dedicated the band's next track, Sad But True, to his fellow heavy rock groups hoping to follow in Metallica's footsteps by performing at the festival in future.After ending their set with a version of Whiskey In The Jar and their track Seek & Destroy, during which dozens of huge inflatable balls embossed with the band's logo were released into the crowd, Hetfield said: "Thank you. Metallica loves you, Glastonbury. You made us feel so good. Thank you for having us."Before leaving the stage, Ulrich took the mic to thank Glastonbury boss Michael Eavis and his family for inviting the band to perform.Glastonbury closes on Sunday with performances from acts including Dolly Parton, Ed Sheeran, and Kasabian.